Physics International Company

Olin Corporation

Other

US Government As Represented by the Secretary of the Army

Kinetic Ceramics, Inc.

Pz Technology, Inc.

Cormac G O'Neill

Parker C Smiley

Charles E Foster

A piezoelectric positioner. First and second piezoelectric stacks are mounted on a rigid frame. A T-lever defining a yoke and a lever arm is disposed so that the yoke overlies the piezoelectric stacks. A compression element is position so as to hold in compression both stacks in-between the frame and the yoke. A programmable voltage source is programmed to provide elongating voltages alternatingly to the first and the second stacks to cause the stacks to alternatingly expand against compressive forces produced by the compression element so as to cause the yoke to rock back and forth and to cause the T-lever arm to swing back and forth. A tool beam is flexibly connected to the T-lever arm. A tool beam restraint restrains movement of the tool beam to back and forth motion in a single direction. In a preferred embodiment a tool is mounted on the tool beam.

Piezoelectric positioner

Ferroelectric transducers each including two cooperating, identically polarized ferroelectric stacks which are excited in opposite polarity. Each transducer includes a yoke assembly for sensing the respective expansions and contractions of the two ferroelectric stacks, mechanically adding these respective expansions and contractions, and applying the sum thereof to a pair of elongated T-levers, which T-levers serve to displace the output element of the transducer.

Ferroelectric transducers

A fluidic valve-operating system has a reciprocally-movable plunger for moving a valve of an internal combustion engine between closed and opened conditions. A main circuit has feed and return paths for flow of hydraulic fluid from a reservoir to the plunger and a pump interposed in the feed path and driven by the engine. A breather circuit has feed and return paths for flow of hydraulic fluid from an accumulator to the plunger. A control valve interposed in the feed and return paths of the respective main and breather circuits is actuatable by a piezoelectric valve for switching each of the main and breather circuits between pressure supply and return flow modes with respect to the plunger. The main circuit when switched to its pressure supply mode applies a drive pressure to the plunger which varies proportionally with the speed of the engine to accelerate the plunger along a drive stroke to move the valve form its closed toward its opened condition. The breather circuit allows pressure relief when the plunger has moved a portion of its total stroke. A chamber containing a gas is connected in flow communication with the pump via a piston to provide a variable pressure spring for applying a return pressure to the plunger which varies proportionally with engine speed, opposes but is less than the drive pressure and causes deceleration and return of the plunger to its initial position when main and breather circuits are in return flow modes.

Hydraulic valve-operating system for internal combustion engines

A fuel injection control system for an internal combustion engine utilizes a fuel injection pump in which the pump cylinder is in fluid communication with the fuel injection nozzle and a piezoelectric actuated spill valve. A cam drive actuates the pump piston to achieve a constant velocity during the pumping cycle (constant velocity relative to degrees of rotation of the engine crankshaft). An index wheel connected to either the engine crankshaft or the pump camshaft is used in conjunction with an initial position detector, angular position detector and a pump control unit to close and open the spill valve at predetermine positions of the pump piston during the pumping cycle. The pump control unit includes a computer connected to various engine parameter transducers to adjust the closing and opening of the spill valve to achieve a desired fuel injection volume.

Variable stroke, electronically controlled fuel injection control system

A method and apparatus for achieving optimized efficiency combustion in a diesel internal combustion engine utilizes a cylinder pressure detector which measures peak cylinder pressure relative to crankshaft timing and compares it with a speed-load-timing map comprising several engine parameters including engine speed and engine load in order to compensate for various unknown combustion characteristics of the fuels to be used in compression ignition engines, and automatically adjusts fuel injection timing for optimum efficiency.

Closed loop diesel engine control

A fuel injection system wherein the fuel pressure can be varied or adjusted n accordance with different engine loading conditions. The system includes an accumulator and a source of high-pressure gas for raising the accumulator pressure in accordance with step increases in the fuel pressure. A pressure-operated piston valve is provided to communicate the accumulator with the gas pressure source or with an atmospheric vent, as necessary to raise or lower the accumulator pressure.

Variable pressure fuel injection system

An electroexpansive linear actuator utilizes a sagittal tension member to amplify linear motion in which the electroexpansive member is placed in compression between a fixed base support and a lever support member hingedly connected to the fixed base. One end of the sagittal tension member is attached to the fixed base while the other end is attached to the lever support member distal the hinge point. The device to be actuated is connected proximate the midpoint of the sagittal tension member and moves perpendicular to the longitudinal axis of the sagittal tension member when the electroexpansive member expands and contracts. A second embodiment of the actuator utilizes a second lever support arm instead of the fixed base as a bearing support for the other end of the electroexpansive member.

Sagittally amplified piezoelectric actuator

A housing having an inlet port and an outlet port utilizes a variable volume cavity connected to the housing and includes a device for limiting the volume of the cavity which is alternately filled through the inlet port and exhausted through the outlet port using a spool valve. The spool valve is arranged to prevent continuous communication of fluid between the inlet and outlet ports. The volume of the variable volume cavity can be varied using electro-expansive or piezoelectric apparatus. The spool valve is reciprocated between the inlet and outlet ports using an electromechanical device and a motion amplifier.

Micro-metering system

An electromotive actuator comprises a hollow cylinder within which is an electroexpansive body having attached to each end a metal cup with slotted sides. Inside of each cup there is positioned an electroexpansive disc which, in the absence of excitation, causes the slotted sides, which are called fingers hereinafter, to bend outward, and in the presence of excitation enables them to return to their original position. In the absence of excitation the fingers clamp tightly against the inner surface of the cylinder and in the presence of excitation they spring inwardly and release that surface. By sequencing the excitation of the respective discs and the central body in one embodiment of the invention, the assembly can be made to move in either direction and thereby move an externally extending rod. In another embodiment of the invention, by properly sequencing the excitation of the discs and central body, high torque and fine angular resolution may be obtained.

Electromotive actuator

A fuel pump for providing fuel at relatively high pressure is activated by gas pressure, created during the compression stroke of an internal combustion engine. The pump includes a piston and a hollow plunger which are biased by a single spring in opposite directions. The piston, which is exposed to gases in the engine's cylinder, is urged, by the gas pressure in the cylinder during the compression stroke, to move upwardly. A limit is placed on the piston's upward stroke. When reaching the upward limit the pressure which is applied to fuel in a fuel chamber is only a function of the force applied by the spring to the plunger. When fuel ejection is enabled, the spring pushes the plunger toward the fuel chamber to eject the fuel therefrom. Toward the end of the exhaust stroke the piston moves toward the engine cylinder, forcing the plunger to move in the same direction until the latter's travel is limited by limiting means. Fuel is then injectable into the fuel chamber for subsequent ejection.

Gas-actuated fuel pump wherein the pump piston is driven by a spring

A fuel injection system for an internal combustion engine is described, which provides for independent, flexible control of timing as well as quantity of fuel injected. The system is programmable for torque shaping and adaptable to a wide range of engine sizes. It uses piezoelectric valves for controlling injection timing, a shuttle, fuel meter and a gas driven high pressure pump for injecting the fuel into the cylinders.

Fuel injection pumps for internal combustion engines

By filling the container of a piezoelectric stack with a dielectric fluid under sufficient pressure, or applying sufficient pressure to a solid dielectric, to maintain dielectric particle velocity and piezoelectric particle velocity substantially spaced, dielectric breakdown with consequent arc over and destruction of the piezoelectric stack is prevented.

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Walnut Creek, CA, United States of America

Cormac G O'Neill